Document data, which is generated by various application programs (regardless of whether the data is raster data or vector data), is converted by a printer driver into print data corresponding to the printer that is the output destination. When the original document data before conversion is in a data format without the concept of resolution, or when the resolution of the document data before conversion is different from the resolution of the printer that is the output destination, the contents of the print data after conversion may include errors with respect to the contents of the print data before conversion. That is to say, the result obtained by outputting the document data onto paper (hereinafter, “paper document”) may include errors with respect to the contents of the original document data before conversion.
Patent Document 1: Japanese Laid-Open Patent Publication No. 2009-272667
When the document data includes a barcode or a two-dimensional code (hereinafter, “barcode, etc.”), the above-described errors may also occur in the barcode, etc.
FIG. 1 is a diagram for describing an example of errors at the time of printing a barcode. In FIG. 1, the rectangles B1, B2, B3, B4, B5, and B6 indicate black lines (bars) of a barcode. An input coordinate system is the coordinate system of the barcode included in the document data. An output coordinate system is the coordinate system corresponding to the resolution of the printer that is the output destination. Each grid in the lattice in FIG. 1 expresses one dot in the output coordinate system.
In the input coordinate system, both the left and right sides of the rectangle B2, the right side of the rectangle B4, and both sides of the rectangle B6 do not match the separator lines of the dots. This kind of situation occurs, for example, when the input coordinate system is in units of inches, or when the resolution of the input coordinate system is different from the resolution of the output coordinate system. In this case, the printer driver corrects the width of each rectangle so as to match the output coordinate system. For example, the rectangle B2 and the rectangle B6 are expanded in directions of both sides and corrected to be three dots. Furthermore, the rectangle B4 is contracted in the right direction and corrected to be three dots. By making such mechanical corrections, the barcode after being printed will have errors with respect to the barcode included in the document data.
Furthermore, FIG. 2 is a diagram for describing an example of errors at the time of printing a two-dimensional code. In FIG. 2 also, according to the same principle as that described with reference to FIG. 1, errors may occur between the two-dimensional code in the input coordinate system and the two-dimensional code in the output coordinate system.
The errors illustrated in FIGS. 1 and 2 may affect the operation of reading the barcode, etc. printed on a paper document after being output. That is to say, it may not be possible to correctly read the proper value expressed by the barcode, etc.